The bill, which received the support of House Speaker John Boehner, passed Wednesday evening by a vote of 229-191.

Sacramento-area Democrats including Doris Matsui, Ami Bera and John Garamendi opposed the legislation.

"It creates a water war, (it) does not solve the problems," Rep. Garamendi told KCRA 3. "It simply steals water from the environment and others in the north."

Republicans said the bill would allow more water to be pumped out of the Sacramento-San Joaquin Delta by undoing federal environmental protections for an endangered species of fish known as the delta smelt.

The finger-sized fish sometimes become trapped and killed in the huge pumps that supply the canals.

"What has hurt the farmers is billions of gallons of water for the delta smelt," Rep. Tom McClintock, R-Granite Bay, told KCRA 3.

However, at a news conference in Sacramento, the head of the federal government's top water-supply agency said that is not true, at least not for the current drought.

"We haven't had any restrictions related to delta smelt since April of last year," said Michael Connor, commissioner of the U.S. Bureau of Reclamation.

Connor told reporters most of the pumps near Tracy have been shut off in order to keep the water in the Delta from becoming too salty for irrigation and drinking.

"We've been operating to the water quality standards up until this time and other obligations that we have, but we haven't restricted the pumping operations yet due to the Endangered Species Act," Connor said.

Still, that could change at any time.

Federal Fish and Wildlife Service officials said they were increasing their monitoring of the smelt to at least twice a week because of approaching rain.

"If there is substantial rain that increases Delta flows and the turbidity of Delta waterways, delta smelt could move closer to the water project diversions," according to a news release issued by the Fish and Wildlife Service.